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Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions
Published on: June 13, 2015
Chang'e-6 farside anorthosites indicate hemispherically comparable magma ocean solidification.
Zeling Wang1,2, Haojie Chen1,2, Yi Chen3,4
1State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China.
Nature Communications
|May 15, 2026
Summary
Lunar magma ocean (LMO) solidified similarly across the Moon, forming comparable crusts. Farside anorthosite clasts show evidence of later reworking, explaining the compositional differences between lunar hemispheres.
Area of Science:
- Lunar geology
- Planetary science
- Geochemistry
Background:
- Ferroan anorthosites (FANs) are key to understanding the Moon's crust formation during the lunar magma ocean (LMO) stage.
- Remote sensing indicates compositional differences between the lunar nearside and farside highlands.
- Uncertainty exists whether this dichotomy stems from asynchronous LMO solidification or later crustal alteration.
Purpose of the Study:
- To investigate the composition and age of farside anorthosites.
- To determine if the lunar crust is compositionally similar across hemispheres.
- To constrain the timing of lunar magma ocean solidification and post-magma ocean processes.
Main Methods:
- Petrological, geochemical, and geochronological analysis of farside anorthosite clasts from the Chang'e-6 mission.
- Mineralogical and compositional comparison with nearside samples.
- High-precision lead-lead dating of zircon.
Main Results:
- Farside anorthosite clasts are mineralogically and compositionally similar to nearside FANs, suggesting a shared origin from the LMO.
- A zircon-bearing domain shows evidence of thermal reworking and metasomatism by KREEP-rich magma.
- Lead-lead dating of zircon constrains a reworking event to 4,410 ± 8 Ma.
Conclusions:
- The primary lunar crust was likely comparable across both hemispheres, originating from the LMO.
- The observed crustal dichotomy is attributed to post-LMO thermal reworking and metasomatism, not asynchronous solidification.
- This study provides a chronological benchmark for farside LMO solidification and insights into lunar crustal evolution.
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